A metabolic flux analysis, which is also referred to as a flux balance analysis, is a technique for predicting intracellular metabolic flux distributions by construction of a stoichiometric model of intracellular biochemical reactions and linear optimization. This technique has been used in research into the abilities of biochemical reaction systems in microorganisms or for predictiing intracellular metabolic flux distributions under different external conditions (Non-patent documents 1, 2 and 3). It has also been reported that a stoichiometric model was constructed for Escherichia coli (Non-patent documents 4 and 5). Also known is an example of using such a stoichiometric model in metabolic engineering for lysine production for Corynebacterium glutamicum, which is used in amino acid production (Non-patent document 6). In addition, a large number of theoretical or experimental methods for metabolic flux analyses and their applications have been reported (Non-patent documents 7, 8, Patent documents 1, 2 and 3). Patent document 1 discloses a method for predicting a gene required for growth based on a stoichiometric model. Patent document 2 discloses a technique for genetically and evolutionarily changing cells to impart optimal functions to the cells. Further, Patent document 3 discloses a method for applying limitations of qualitative kinetic information, limitations of qualitative control information and limitations based on DNA microarray experimental data under different conditions to a stoichiometric model. Although all of these are methods for predicting more desirable intracellular metabolic flux distributions, no method has been disclosed for theoretically predicting a flux as a target for directly improving cellular substance production.
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